Earth Rocks!
Noun
hard, black, often glassy, volcanic rock
Resulting from a volcanic eruption 60 million years ago, the Giant's Causeway is an area of about 40,000 interlocking basalt columns.
Adjective
having flat polished surfaces occurring naturally on a crystal
Located in Mexico, the cave is covered with perfectly-faceted crystalline blocks and huge crystal beams that jut out.
Noun
deposits of rocks or minerals of a particular origin
These beautiful formations were formed from lime leaching from the sand and by rain cementing the lower levels of the dune into soft limestone.
Noun
process by which something is preserved in the earth
The fossil record is quite incomplete, mainly because most organisms decompose before sediments can cover the body and fossilization can occur.
Noun
landform of eroded limestone including ridges, towers, underground streams, etc.
These karst formations in southwest China are tall rocks that seem to emanate from the ground in the manner of stalagmites.
Noun
land formation with steep edges and a flat top
With two sandstone spires soaring from a mesa, not only is Chimney Rock a spectacular place; it also provides a fascinating glimpse into the ancient people who lived in that region more than a thousand years ago.
Verb
change the shape or outline of something by natural processes such as erosion
The "Eye of Africa," easily visible from space, is now thought to be a symmetrical uplift sculpted and laid bare by erosion.
Noun
tapering structure hanging like an icicle from the roof of a cave
The Jeita Grotto is a compound of crystallized caves located in Beirut. It is home to one of the biggest stalactites in the world, hanging 8.2 m (27 ft) from the ceiling.
Adjective
having a wavelike appearance or form
Located in the USA near the Arizona and Utah borders, the Wave is famous for its colorful, undulating forms. A rugged, trackless hike is required to reach it.